The Summary of Physics Restored

63The heat rising from earth's bosom, moist and impure through the taint of mingled earth and water, corrupts. The purest celestial heat, however, generates by rousing, expanding and urging into life the implanted heat hidden in the seeds of things, concealed in their centre like nature's secret. Because those two heats are of like nature, they gently come together in the work of generation and unite inseparably until they issue in life and abundant growth.